材料科学および工学ジャーナル

Here we report on the successful deposition of stellite-6 coatings by Cold Gas Spray (CGS) technology and their tribological properties in correlation with the as-sprayed structure.The deposits were dense and showed satisfactory interparticle bonding. The deformation mechanisms involved within the process are evaluated with regard to the particle shape and dendritic deformation at the boundaries and also internal structural defects.
Despite the lower hardness of CGS coatings compared to HVOF ones, they displayed relatively good wear rates under both abrasive and sliding conditions. The wear mechanisms are discussed mainly in terms of local oxidation and possible martensitic phase transformation of stellite.

Uranium-zirconium alloy is considered main ingredient for making metallic fuel for Fast Breeder Reactor. Also, Zr-rich U-Zr alloys find applications in dispersion fuel for advance PWR. In this work investigations were carried out on the zirconium rich uranium-zirconium alloys (i.e. U-50wt%Zr, U- 60wt%Zr and U-70wt%Zr) in as-cast as well as in heat treated conditions. Microstructural and dilatometric studies were carried out along with X-ray Diffraction Analysis (XRD) to evaluate the phase content as well as the phase transformation behavior of these alloys under different heat treated conditions.